Abstract: Objective To study the different gene expressions of cap stage (E14.5) and early bell stage (E18.5) in murine molar. Methods The mouse molar germ at E14.5 and E18.5 were removed. Gene chip was used to obtain the different gene expressions. Results There were 76 differently expressed genes, 71 up-regulated genes and 5 down-regulated genes. Conclusion In molar germ of early bell stage (E18.5), genes related to cell metabolism, differentiation, formation of polarity, regulating immune response, regulating transcription and translation, signaling molecules and receptors, stress response are up-regulated dramatically. Genes related to cell apoptosis and amino acid metabolism kinases are down-regulated.